A man who violently mugged a 16-year-old schoolboy in Norwich has been sent to a young offenders' institute for four years.

Connor Folkard-Moore, 19, had taken cocaine, ketamine and alchohol before wandering the edge of the city centre 'ruminating', Norwich Crown Court heard yesterday.

He admitted headbutting a cleaner on his way to work in a failed mugging, before punching a schoolboy in the face and stealing his rucksack, iPhone and camera.

Chris Youell, prosecuting, said the victims were attacked on December 6.

It was around 5.35am when Folkard-Moore, of Ruskin Road, Norwich, spotted his first victim in Rouen Road.

Mr Youell said the victim, a cleaner, tried to walk past Folkard-Moore.

'He didn't want to talk to him,' said Mr Youell. 'He was trying to avoid him, but Mr Folkard-Moore blocked his route, walked directly up to him and demanded money.'

He told the court Folkard-Moore had his right hand behind his back and claimed to have a knife, though there was no evidence he had one.

When the victim refused to hand over cash Folkard-Moore headbutted him, knocking the victim's glasses off, and they both fell to the floor.

Folkard-Moore fled empty-handed and the victim got a taxi to work where he called police.

Around half an hour later Folkard-Moore happened upon a 16-year-old schoolboy who had left home early to go on a school trip to Birmingham.

The schoolboy was walking to a coach pick-up point in Newmarket Road, and was nearing Ber Street when he was attacked.

Mr Youell said the schoolboy had been talking to a classmate, who was already on the coach, on his iPhone when he felt a punch to the left side of his head.

He was punched two more times and fell into a bush.

The schoolboy offered to hand his belongings over to Folkard-Moore and described him as talking in a 'chavvy slang voice', added Mr Youell.

His iPhone was stolen, together with his £50 back pack containing a £500 digital SLR camera, a £50 fish eye lens, his packed lunch and his pencil case which contained art equipment.

The schoolboy suffered a large swelling to his eyebrow area, cuts inside his mouth and a small cut to his left hand.

He ran home, woke his mother and called police, who checked CCTV and arrested Folkard-Moore.

Folkard-Moore gave no comment interviews and was not identified by the victims, as the cleaner was short-sighted and the schoolboy did not see his face.

But DNA taken from the cleaner's jacket matched Folkard-Moore's.

Michael Clare, defending, described the incidents as 'nasty' but said Folkard-Moore was not a ringleader, it was not pre-planned, he was not wearing a disguise and he showed evidence of remorse.

Judge Anthony Bate, sentencing, said: 'You were disruptive at school, had an entrenched drug and alcohol habit and on the night in question had taken alcohol, ketamine and cocaine then went round the city ruminating on events.

'Those victims were simply in the wrong place at the wrong time when they came across an angry young man who was willing to assault them.'

Folkard-Moore, who pleaded guilty to assault with intent to rob and robbery, was sentenced to four years in a young offenders institute and ordered to pay £120 costs.